1、 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 Navistar, Inc. AUGUST 2009 Page 1 of 3 NAVISTAR, INC. CEMS (CORPORATE ENGINEERING MATERIAL SPECIFIC
2、ATION) NUMBER: CEMS BT-49 TITLE: Determination Of Molybdenum Disulfide In Lubricants CURRENT ISSUE DATE: August 2009 WRITTEN/REVIEWED BY: Materials Engineering APPROVED BY: Materials Engineering SUPERSEDES ISSUE OF: October 2001 PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRENT REVISION T
3、his specification may involve hazardous materials, equipment, and procedures. This specification does not purport to address all of the safety issues associated with its use. The user is responsible to consult appropriate safety and health practices and to determine the applicability of regulatory l
4、imits prior to use. Change Notice: Replaced “International Truck and Engine Corporation” with “Navistar, Inc.” per corporate directive. 1.0 SCOPE This method covers a test procedure for determining molybdenum disulfide in lubricants by atomic absorption spectroscopy. 2.0 APPARATUS 2.1 Atomic-absorpt
5、ion Spectrophotometer, for use at 313.1 nm. 2.2 Molybdenum hollow-cathode lamp. 2.3 Pressure-reducing valves. 2.4 Analytical balance with a sensitivity of 0.1 mg. 2.5 Hot plate. 2.6 Fume hood. 2.7 Beaker, 250 ml, Pyrex or equivalent. 2.8 Watch glass, 90 mm diameter, Pyrex or equivalent. 2.9 Volumetr
6、ic flask, glass, 100 ml. 2.10 Volumetric flask, glass, 1000 ml. 2.11 Spatula, stainless steel, semi-micro. 2.12 Funnel, glass, 75 mm diameter, 150 mm stem. 2.13 Graduated cylinder, glass, 50 ml. 2.14 Pipette, glass, volumetric, TD, 10 and 20 ml. 3.0 MATERIALS 3.1 Oxidant: Nitrous Oxide, Commercial G
7、rade. 3.2 Fuel: Acetylene, Commercial Grade. 3.3 Distilled water per ASTM D 1193, Type II. 3.4 Sulfuric acid, ACS reagent grade, concentrated, H2SO4. 3.5 Nitric acid, ACS reagent grade, concentrated, HNO3. 3.6 Molybdenum disulfide, 98% MoS2 minimum assay. 3.7 Pipette, Pasteur, glass, 153 mm. 3.8 Mat
8、erial Blank for Standards preparation: Material having a composition similar to the analysis sample but containing less than 0.001 mass percent molybdenum. NUMBER: CEMS BT-49 TITLE Determination Of Molybdenum Disulfide In Lubricants CURRENT ISSUE DATE: August 2009 This document is restricted and may
9、 not be sent outside Navistar, Inc, or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 Navistar, Inc. AUGUST 2009 Page 2 of 3 4.0 PREPARATION OF STANDARDS 4.1 Weigh the following amounts of MoS2 and the Material Blank into
10、 three 250 ml beakers. Beaker M0S2, grams Material Blank, grams 1 0.10 0.001 4.90 2 0.15 0.001 4.85 3 0.20 0.001 4.80 4.2 Place the beakers containing the standards in a fume hood and add 20 ml of H2SO4 to each beaker. Allow to stand at room temperature for ten minutes. CAUTION: With some samples, t
11、here may be an immediate reaction with the H2SO4. Let any reaction subside before performing Step 4.3. 4.3 Add 20 ml of HNO3 to each beaker, cover beakers with watch glasses and place samples on a cold hot plate. 4.4 Turn on hot plate and digest samples until the solution remains clear. Cautious per
12、iodical additions of 1 to 3 ml HNO3 with a glass pipette will be necessary until the digestion is complete. 4.5 Quantitatively transfer the contents of each beaker to individual 1000 ml volumetric flasks and dilute to the mark with distilled water. NOTE: Standards may be retained for up to three mon
13、ths for future use on similar materials. 5.0 PROCEDURE 5.1 Weigh 5 + 0.001 g of test sample into a 250 ml beaker. 5.2 Digest and dilute sample as described under ”Preparation of Standards, Steps 4.2 thru 4.5. 5.3 Operate the atomic-absorption spectrophotometer per manufacturers instructions for use
14、at 313.3 nm, using a nitrous oxide/acetylene flame. 5.4 Pipette 20 ml aliquots from the flasks in Step 5.2 to 100 ml volumetric flasks and dilute to the mark with distilled water and record absorbance, at 313.3 nm, of the standard and test sample dilutions using a Nitrous Oxide flame. NOTE: If the S
15、pectrophotometer is equipped with a data processor, the concentration of MoS2 may be determined directly. See the manufacturers instructions for procedure. 6.0 CALCULATION 6.1 Plot a graph of mass percent M0S2 versus absorbency for the standards. Mass % MoS2 in standards: Mass % = wt. M0S2 x Purity
16、of M0S2 x100 Wt. Material Blank + wt. M0S2 6.1.1 If the absorbency of the test sample does not fall on the calibration curve, adjust aliquot and final dilution volume as per Step 5.4, to make absorbency fall on calibration curve. NUMBER: CEMS BT-49 TITLE Determination Of Molybdenum Disulfide In Lubr
17、icants CURRENT ISSUE DATE: August 2009 This document is restricted and may not be sent outside Navistar, Inc, or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 Navistar, Inc. AUGUST 2009 Page 3 of 3 6.2 Plot the absorbenc
18、y of the test sample on graph for the standards and determine mass percent MoS2 in sample from group. Mass % = MoS2 in sample = A 20100BC A = Value, mass % MoS2, obtained from graph. B = Final volume to which sample is diluted, Step 5.4. . C = Aliquot of sample from Step 4.5 used in Step 5.4. . NOTE: Mass percent molybdenum in the sample may be calculated as follows: Mass % M0 in Sample = mass % Molybdenum disulfide (MoS2) in sample x 0.599 7.0 REPORT Mass percent molybdenum disulfide (MoS2) or molybdenum (Mo) to the nearest 0.005 mass percent.
